I would'nt do that either The first time I saw it done I thought it was cool for about 10 minutes. Then I came to the realization that it is dumb. Do it if you want, it is your bike. The effort involved in doing it get's you no where except to making your bike look silly. I like beer as much as the next guy, but bottle caps belong in 2 places. On the bottle, or in the garbage.